<template>
  <div class="spec-preview">
   
    <img :src="skuInfo.skuDefaultImg" />
    <!-- 小图片增加事件 -->
    
    <div class="event" @mousemove="move"></div>
    
    <div class="big">
      <img :src="skuInfo.skuDefaultImg"  :style="{ left: -2 * left + 'px', top: -2 * top + 'px' }"/>
    </div>
    
    <div class="mask" :style="{left:left+'px',top:top+'px'}"></div>
    
  </div>
</template>

<script>
import { debounce } from 'lodash';
import { mapGetters } from 'vuex'
  export default {
    name: "Zoom",
    data() {
      return {
        left: 0,
        top: 0
      };
    },
    computed:{
      ...mapGetters('detail',['skuInfo'])
    },
    methods:{
      move:debounce(function(event){
         let x = event.offsetX - 100;
          if (x < 0) x = 0;
          if (x > 200) x = 200;
          let y = event.offsetY - 100;
          if (y < 0) y = 0;
          if (y > 200) y = 200;
          this.left = x;
          this.top = y;
      },1000/90)
      // move(event){
      //     let x = event.offsetX - 100;
      //     if (x < 0) x = 0;
      //     if (x > 200) x = 200;
      //     let y = event.offsetY - 100;
      //     if (y < 0) y = 0;
      //     if (y > 200) y = 200;

      //     this.left = x;
      //     this.top = y;
      // }
    }
  }
</script>

<style lang="less">
  .spec-preview {
    position: relative;
    width: 400px;
    height: 400px;
    border: 1px solid #ccc;

    img {
      width: 100%;
      height: 100%;
    }

    .event {
      width: 100%;
      height: 100%;
      position: absolute;
      top: 0;
      left: 0;
      z-index: 998;
    }

    .mask {
      width: 50%;
      height: 50%;
      background-color: rgba(0, 255, 0, 0.3);
      position: absolute;
      left: 0;
      top: 0;
      display: none;
    }

    .big {
      width: 100%;
      height: 100%;
      position: absolute;
      top: -1px;
      left: 100%;
      border: 1px solid #aaa;
      overflow: hidden;
      z-index: 998;
      display: none;
      background: white;

      img {
        width: 200%;
        max-width: 200%;
        height: 200%;
        position: absolute;
        left: 0;
        top: 0;
      }
    }

    .event:hover~.mask,
    .event:hover~.big {
      display: block;
    }
  }
</style>